The present invention relates to a drainage filter system for a fishpond and more particularly to an auto-flushing drainage filter system fastened to a fishpond at the bottom to automatically circulate the water through a drum filter and also to automatically flush the drum filter at a predetermined frequency.
In farming fishes in fishponds, the fishponds must be regularly cleaned so that the optimum natural conditions for fishes can be maintained. However, it is neither easy nor economic to completely change the water of a fishpond. In order to keep a fishpond clean at less cost, a drain filter is commonly used. If a drain filter is used, the filter materials (such as charcoals, pebbles, sands, palm coirs, etc.,) of the drain filter should be replaced regularly. Forgetting to replace the filter materials will deteriorate the performance of the drain filter and shorten its service life.